The present invention relates to an actuation recorder for recording the actuation profile of an inhalation device. In particular, the invention relates to an actuation recorder for use with a metered dose inhaler by means of which medicament contained in an aerosol container may be administered to a patient.
It is well known to treat patients with medicaments contained in an aerosol, for example, in bronchodilator therapy. It is also known to use for such therapy, medicaments which are contained in an aerosol and are administered to a patient by means of an inhalation device comprising a tubular housing or sleeve in which the aerosol container is located and an outlet tube leading out of the tubular housing. The aerosol containers used in such inhalation devices are designed to deliver a predetermined dose of medicament upon each actuation by means of an outlet valve member at one end which can be opened either by depressing the valve member while the container is held stationary or by depressing the container while the valve member is held stationary. In the use of such devices, the aerosol container is placed in the tubular housing with the outlet valve member of the container communicating via a support with the outlet tube, for example a nozzle or mouthpiece. When used for dispensing medicaments, for example in bronchodilation therapy, the patient then holds the housing in a more or less upright condition and the mouthpiece or nozzle of the inhalation device is placed in the mouth or nose of the patient. The aerosol container is pressed towards the support to dispense a dose of medicament from the container which is then inhaled by the patient.
It may be understood that effective delivery of medicament to the patient using an inhalation device as described above is to an extent dependent on the patient""s ability to co-ordinate the actuation of the device (e.g. firing of the aerosol) with the taking of a sufficiently strong inward breath. The required co-ordination can present difficulties to some patients, with the risk that these patients do not receive the appropriate dose of medicament. It is, thus, desirable to provide a means for the patient to monitor their correct usage of the inhalation device. Such means might be designed for everyday usage or for use in a system for training patients in the correct usage of the inhalation device.
Various training systems have been described in the prior art. These typically involve the use of customised inhalers or apparatus incorporating or connected to various means for providing the patient with information about their correct (or incorrect) usage of the inhaler. Examples of such customised inhalers or apparatus include the inhaler described in WO93/12823 which incorporates various sensors and microprocessors; the inhalation apparatus described at U.S. Pat. No. 4,495,944 which includes various visual indicators to guide the patient; the biofeedback and training evaluation system described at U.S. Pat. No. 4,984,158; and the apparatus and visual display method described at U.S. Pat. No. 5,333,106.
A disadvantage associated with the use of such customised inhalers and apparatus is that the patient is trained with this customised equipment but then uses a standard inhalation device on a regular basis which is likely to have different shape, size, look and feel characteristics. In essence, therefore, the training system trains the patient to operate the customised equipment rather than their own inhalation device which they use regularly.
The Applicants have now found that this disadvantage may be overcome by the use of an actuation-indicator and system which is employed as an add-on to a standard inhalation device. The patient may thus be trained in the use of a device which is identical to (or indeed is) the device they take home with them after the training session for everyday use.
Whilst the actuation-indicator of the present invention is connectable to electronic visual or audio display means, there is no requirement for any electrical connection on the device itself.
According to one aspect of the present invention there is provided a dispenser for dispensing medicament or placebo comprising a housing; locatable within said housing, a container having a dispensing aperture, wherein said container is movable relative to the housing to enable dispensing therefrom; and an actuation-indicator for detecting movement of the container relative to the housing, said actuation-indicator comprising a first part defining a pocket having an outlet therefrom and a second part movable relative to said first part to create a pressure change at said outlet.
In one aspect, said first and second parts jointly define a chamber and the second part comprises a flexible wall or membrane which is resiliently deformable to create said pressure change.
In another aspect said pocket of the first part is shaped for snug receipt of said second part to define a piston arrangement.
Suitably, the outlet is in communication with a pressure gauge to measure the pressure change. Preferably, the pressure gauge comprises a pressure transducer.
Suitably, the actuation-indicator additionally comprises a third part defining a second pocket having an outlet therefrom; and a pressure change channel for channelling airflow from the housing to the second pocket to create a pressure change at the outlet. This third part may be employed to monitor airflow through the housing of the dispenser. In a preferred aspect, the pressure change channel is at least partly foldable into the housing. The pressure change channel may comprise various grooves or tracks.
In one aspect, the actuation-indicator is mountable on the exterior of the housing. Suitably, the actuation-indicator comprises a carrier sleeve which is mountable on the exterior of the housing and separable therefrom. Preferably, the housing has a tubular portion, the container is movable within said tubular portion and said carrier sleeve is snugly receivable by the tubular portion.
One or more guide elements may be provided to the tubular portion and/or the carrier sleeve to guide the receipt of the carrier sleeve by the tubular portion. The guide elements may, for example, be mechanical guides such as tongue and groove arrangements. The guide elements may also for example, be visual guides such as colour coding arrangements.
A first end of the tubular portion may have a lip to prevent over-receipt of the carrier sleeve. The lip and the leading end of the carrier sleeve may be shaped for relative engagement.
The dispenser may additionally comprise a cap which is mountable on the container, wherein movement of the cap results in movement of the second part.
Suitably, the cap has a peg which engages said second part.
In another aspect, the actuation-indicator is mountable on the container.
Suitably, the container is an aerosol container. Preferably, the aerosol container provides measured doses.
Suitably, the dispenser is actuable in response to the breath of a user.
According to another aspect of the present invention there is provided a system for training users in the operation of a dispenser comprising a dispenser as described above in communication with a unit capable of visually or audibly indicating actuation of the dispenser. The unit may also be configured to enable visual or sound indication of the pressure profile associated with the inhalation pattern of the patient and the degree of synchronisation between the actuation and inhalation profiles.
According to a further aspect of the present invention there is provided the use of a system described above for training the user in the operation of the dispenser.
According to another aspect of the present invention there is provided an actuation-indicator for use with a dispenser comprising a housing and a container which is movable relative to said housing, said actuation-indicator comprising a first part defining a pocket having an outlet therefrom and a second part movable relative to said first part to create a pressure change at said outlet.
In one aspect, said first and second parts jointly define a chamber and the second part comprises a flexible wall which is resiliently deformable to create said pressure change.
In another aspect, said pocket of the first part is shaped for snug receipt of said second part to define a piston arrangement.
According to a further aspect of the present invention there is provided a kit of parts comprising an actuation-indicator as described above and a dispenser comprising a housing and a container which is movable relative to said housing. The kit of parts can also comprise means for connecting the actuation-indicator to an information processor such as a computer. The information processor typically comprises a multi-media display and is controllable by suitable software.
The dispenser may be used for dispensing medicament or placebo.